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arXiv · 2211.00278

Tidal Deformability of Neutron Stars in Unimodular Gravity

Rui-Xin Yang·Fei Xie·Dao-Jun Liu
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Abstract

Unimodular gravity is a modified theory with respect to general relativity by an extra condition that the determinant of the metric is fixed. Especially, if the energy-momentum tensor is not imposed to be conserved separately, a new geometric structure appears with potentially observational signatures. In this paper, we study tidal deformability of compact star in the unimodular gravity under the assumption of non-conserved energy-momentum tensor. Both the electric-type and magnetic-type quadrupole tidal Love numbers are calculated for neutron stars with polytrope model. It is found that the electric-type tidal Love numbers are monotonically increasing, but the magnetic-type ones are decreasing, with the increase of the non-conservation parameter. Compared with the observational data from detected gravitational-wave events, a small negative non-conservation parameter is favored.

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Rui-Xin Yang, Fei Xie, Dao-Jun Liu. 2022-11-01. Tidal Deformability of Neutron Stars in Unimodular Gravity. https://arxiv.org/abs/2211.00278

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